1. Field of the Invention
This invention relates to a mold-thickness adjustment mechanism for toggle type vertical molding machine in which any one of a pressure-receiving plate or a movable platen which an end of a tie-bar is clamped and fixed is moved in the advancing and/or retreating directions by turning an adjusting nut, whereby mold-thickness adjustment is performed.
2. Detailed Description of the Prior Art
It has been known a mold-thickness adjustment mechanism in which while ends of four pieces of tie-bar constituting a mold-clamping mechanism are secured to a fixed plate, the other ends are formed into threaded shafts, and are clamped and fixed to the pressure-receiving plate by means of the adjusting nuts (a tie-bar nut) with a toothed wheel of an outer surface of the pressure-receiving plate, and toothed wheels with a large diameter for mold-thickness adjustment which are moved in the advancing and/or retreating directions together with the movable platen on the pressure-receiving plate by turning those adjusting nuts through the toothed wheel are provided together with a toothed wheel-driving motor of a side of the pressure receiving plate on a central of the outer surface of the pressure-receiving plate.
This prior mold-thickness adjustment mechanism is engaged with the toothed wheel of the adjusting nut screwed to each tie-bar nut and the toothed wheel with the large diameter directly or through intermediate toothed wheels with a small diameter individually. Since most of the pressure-receiving plate, the movable platen and the fixed plate are based on a square plate body, the toothed wheel with the large diameter is accommodated therein, whereby it can not be extruded in a horizontal molding machine, however, since both of a position which insertion or the like is performed on a base and a position which injection is performed are provided on the base, the mold-clamping mechanism should be installed approaching toward an injection device side, moreover, an oblong plate body is used for the pressure-receiving plate in a vertical-rotary type molding machine.
When using the toothed wheel with the large diameter engaging with each tie-bar directly for the mold-thickness adjustment mechanism of such vertical molding machine in the same way as the case of the horizontal molding machine, the toothed wheel with the large diameter 16a is extruded from both sides of the oblong plate body largely as shown in FIG. 1 by a phantom line, so that the toothed wheel-driving motor can not be installed on the side portion of the plate body and an inconvenience also is caused in installation of a safety cover.
Moreover, in such toothed wheel with the large diameter 16a as is extruded from the plate body, a support portion is limited within the range of the central portion of the plate body, and since especially, an extrusion region of the toothed wheel with the large diameter can not be supported with an annular spur gear rotating and supporting an inner peripheral side by a number of rollers, a shake in a horizontal rotation tends to cause, and misalignment in an engagement manner is caused for the long term use, so that it can interfere with the smooth horizontal-rotation.
The present invention is devised for solving the prior problems described above, and the object of present invention is to provide a new constitution which has solved an inconvenience where using a mold-thickness adjustment mechanism according to toothed wheels with a large diameter for a toggle type vertical mold-clamping device in which a fixed plate, a pressure-receiving plate and a movable platen or the like is constituted by an oblong plate body, by using the intermediate toothed wheels engaging with a pair of toothed wheels on a tie-bar side.
The present invention for accomplishing the object described above is a toggle type vertical molding machine constituted by forming a fixed plate, a pressure-receiving plate and a movable platen into an oblong shape to insert the movable platen into tie-bars in four corners of the fixed plate and the pressure-receiving plate and to install a mold-clamping device which toggle mechanisms 9 for mold-clamping are provided across the pressure-receiving plate and the movable platen on a base, arranging the pressure-receiving plate in an upper side, wherein while the described-above ends of tie-bars are secured to the fixed plate, the other ends are formed into threaded shafts 5, and are clamped and fixed to the pressure-receiving plate by means of adjusting nuts with a toothed wheel on an outer surface of the pressure-receiving plate, which toothed wheels are in position, and toothed wheels with the large diameter for mold-thickness adjustment which are moved in the advancing and/or retreating directions together with the movable platen on the pressure-receiving plate by turning those adjusting nuts through the toothed wheel are provided together with a toothed wheel-driving motor on the side of the pressure-receiving plate on the central portion of an outer surface of a pressure-receiving plate, and intermediate toothed wheels are arranged between the toothed wheel with the large diameter and a pair of described-above toothed wheels of one side of the pressure-receiving plate to engage each other and to rotate a pair of the toothed wheels at same time by rotation of the intermediate toothed wheels, whereby a diameter of the toothed wheel with the large diameter is constituted approximately equally to a breadth of the plate body of the pressure-receiving plate.
The other one of the present invention is a toggle type vertical molding machine constituted by forming a fixed plate, a pressure-receiving plate and a movable platen into an oblong shape to insert tie-bars 4 in the four corners of the pressure-receiving plate and the fixed plate into the fixed plate and to install a mold-clamping device which the toggle mechanisms for mold clamping are provided across the fixed plate and the pressure-receiving plate on the base, arranging the movable platen 3 in an upper side, wherein while the described-above ends of tie-bars are secured to the fixed plate, the other ends are formed into threaded shafts 5, and are clamped and fixed to the pressure-receiving plate by means of adjusting nuts with a toothed wheel on an outer surface of the pressure-receiving plate, which toothed wheels are in position, and toothed wheels with the large diameter for mold-thickness adjustment which the movable platen are moved in the advancing and/or retreating directions by turning those adjusting nuts through the toothed wheel are provided together with a toothed wheel-driving motor on the side of the pressure-receiving plate on the central portion of an outer surface of the movable platen, and intermediate toothed wheels are arranged between the toothed wheel with the large diameter and a pair of described-above toothed wheels of one side of the pressure-receiving plate to engage each other and to rotate a pair of the toothed wheels at same time by rotation of the intermediate toothed wheels, whereby a diameter of the toothed wheel with the large diameter is constituted approximately equally to the breadth of the plate body of the pressure-receiving plate.
The diameter of the toothed wheel with the large diameter in the described-above constitution is specified depending upon the breadth of the plate body of the pressure-receiving plate or the movable platen, and the diameter of the intermediate toothed wheel becomes the size that the intermediate toothed wheels can engage with both of the toothed wheel with the large diameter and a pair of toothed wheels on one side. The diameter of the toothed wheel with the large diameter in such mold-adjustment mechanism can be formed into a smaller size and to be able to adapt to the plate body narrow in breadth and oblong, whereby the inconvenience due to extrusion of the toothed wheel with the large diameter from the plate body can be solved even the vertical mold-clamping device with the mold-adjustment mechanism according to a group of the toothed wheels can be finished in a compact size at the upper thereof.